Door for vacuum chamber

ABSTRACT

A door for a vacuum chamber is disclosed. The present invention is constructed to prevent the door, for opening or closing an opening which is provided in one surface of a chamber, from being deformed by a bending load generated when a vacuum is created in the chamber, thus enabling a vacuum to be reliably created in the chamber, and reducing the cost of maintenance of the door. The door includes a chamber having in one surface thereof an opening. A door is rotated to open or close the opening of the chamber. A guide plate is fastened to an outer surface of the door in such a way as to be spaced apart from the door by a predetermined interval, and is rotatably coupled at one end thereof to a hinge assembly.

TECHNICAL FIELD

The present invention relates, in general, to a door for a vacuumchamber and, more particularly, to a door for a vacuum chamber, which isused to put an article into the chamber, and is constructed to preventthe door from being deformed by a bending load when a vacuum is createdin the vacuum chamber.

BACKGROUND ART

As is well known to those skilled in the art, methods of using plasma,which is the fourth state of matter, and is distinct from three statesof matter, namely, solid, liquid, and gas, have been widely adopted inall industrial fields.

For example, in order to manufacture semiconductors and flat paneldisplays as well as fluorescent lights and neon lights, which are widelyused in daily life, several manufacturing processes are required. Amongthe manufacturing processes, the process of manufacturing a wafer orsubstrate includes unit steps, such as a dry etching step, a physical orchemical vapor deposition step, a photoresist washing step, etc. Inthese unit steps, plasma is widely used.

Further, the method of using plasma is used to disinfect or sterilizearticles on which the presence of germs is unacceptable, such as medicalinstruments.

The applicant of the present invention has been granted many patents fora plasma sterilizer, which sterilizes an article, such as a medicalinstrument, using hydrogen peroxide, and decomposes the used hydrogenperoxide into nontoxic matter using plasma, prior to discharging thenontoxic matter outside the sterilizer. As shown in FIG. 1, a plasmasterilizer 10 is provided with a vacuum chamber 20, in which a vacuum isformed. A door 30 is mounted to one surface of the chamber 20, and isused for insertion of an article to be sterilized, such as a medicalinstrument, into the chamber.

Only one surface of the chamber 20 is open, and the remainder of thechamber is hermetically sealed. The door 30 is mounted to the opensurface of the chamber so as to open or close it.

A base plate 40, which is open at a central portion thereof, is mountedto the opening of the chamber 20. The door 30 is provided on the frontof the base plate 40 so as to open or close the central opening of thebase plate. The door 30 is coupled at one end thereof to one end of thebase plate 40 via a hinge assembly 50. Thus, as the door 30 rotatesaround the hinge assembly 50 relative to the base plate 40, the chamberis opened or closed.

The door 30 rotates around the hinge assembly 50, thus opening theopening of the base plate 40 and the opening which is provided on onesurface of the chamber 20. The article to be sterilized, such as themedical instrument, is put into the chamber through the openings.Subsequently, the door 30 rotates around the hinge assembly 50 again,thus closing the opening of the base plate 40 and the opening of thechamber 20.

In this state, plasma is generated in the chamber 20, so that thearticle is sterilized.

In this case, in order to sterilize the article using the plasmagenerated in the chamber 20, a vacuum must be created in the chamber 20.As the vacuum is created in the chamber 20, the door 30 is pulledtowards the chamber 20 by external atmospheric pressure.

As such, if the door 30 is repeatedly pulled towards the chamber 20 eachtime the chamber 20 is evacuated, the hinge assembly 50 of the door 30may be deformed due to the load. Thereby, the entire door 30 may bedistorted.

That is, the hinge assembly 50 of the door 30 is mounted to only one endof the door 30. Thus, as the door 30 is pulled inwards relative to thechamber 20 due to the vacuum in the chamber 20, stress concentrates onthe hinge assembly 50. Hence, when the hinge assembly 50 is deformed dueto a load, and thus the door 30 is distorted, the door 30 cannotperfectly close the chamber 20. As a result, it is difficult to create avacuum in the chamber 20.

Therefore, the door 30 must be frequently replaced with a new one, sothat the maintenance cost is increased.

DISCLOSURE Technical Problem

Accordingly, the present invention has been made keeping in mind theabove problems occurring in the prior art, and an object of the presentinvention is to provide a door for a vacuum chamber, which isconstructed to prevent the door, for opening or closing an openingformed in one surface of the chamber, from being deformed by a bendingload generated during the evacuation of the chamber, thus reliablycreating a vacuum in the chamber, and reducing the cost of maintenanceof the door.

Technical Solution

In order to accomplish the above object, the present invention providesa door for a vacuum chamber, including a chamber having in one surfacethereof an opening; a door rotated to open or close the opening of thechamber; and a guide plate which is fastened to an outer surface of thedoor in such a way as to be spaced apart from the door by apredetermined interval, and is rotatably coupled at one end thereof to ahinge assembly.

The door includes fastening holes having a predetermined depth atregular intervals, and the guide plate includes through holescorresponding to the fastening holes, so that a fastening member passesthrough a corresponding through hole and is secured at an end thereof tothe corresponding fastening hole, thus fastening the guide plate to thedoor.

Further, first grooves are formed at regular intervals in a surface ofthe door contacting the guide plate, and second grooves are formed inthe guide plate to correspond to the first grooves in the door, so that,when the guide plate contacts the door, a space having a predeterminedsize is defined between the first and second grooves.

Each of the first grooves in the door is formed around a correspondingfastening hole to have a predetermined depth, and each of the secondgrooves in the guide plate is formed around a corresponding through holeto have a predetermined depth.

Preferably, an elastic member is installed in the space, is secured at afirst end thereof to an inner surface of each of the first grooves inthe door, and is secured at a second end thereof to an inner surface ofeach of the second grooves in the guide plate. The elastic membercomprises a coil spring.

The door further includes a guide bushing having a hole through whichthe fastening member passes. The guide bushing includes a first partwhich passes through a corresponding through hole in the guide plate andslides a predetermined interval in the space, and a second part whichhas a diameter larger than the through hole in the guide plate and isstopped by an outer surface of the guide plate.

When the end of the fastening member is completely fastened to each ofthe first grooves in the door, a predetermined gap is defined betweenthe second part of the guide bushing and the outer surface of the guideplate.

Further, a block is fastened to the guide plate, increases strength ofthe guide plate, and has a hole for guiding the guide bushing.

A base plate, having in a central portion thereof an opening, isprovided on a front of the opening of the chamber, and the door isrotated to open or close the opening of the base plate and the openingof the chamber.

The hinge assembly is mounted to an end of the base plate, and an end ofthe guide plate is rotatably coupled to the hinge assembly.

Advantageous Effects

As described above, the present invention provides a door for a vacuumchamber, which rotates around a hinge assembly provided on one side ofthe door, and which is constructed so that guide plates are provided onthe upper and lower portions of the door in such a way as to be spacedapart from the door by a predetermined interval, and each of the guideplates is rotatably coupled at one end thereof to the fixed hingeassembly, and an elastic member is interposed between the door and thecorresponding guide plate, thus allowing the guide plate to remain in afixed position, even if the door is pulled towards the chamber when thevacuum chamber is evacuated, therefore preventing stress from beingconcentrated on a part of the door coupled to the hinge assembly, andpreventing the hinge assembly from being deformed.

In a detailed description, since the part of the door coupled to thehinge assembly is not deformed due to the concentration of stress, thedoor always reliably closes the opening of the chamber. Thus, plasmatreatment can be smoothly conducted because the vacuum is reliablyformed.

Further, continuous maintenance for the door is not required, thusreducing maintenance costs.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view showing a conventional plasma sterilizer,and showing the coupling of a vacuum chamber with a door;

FIG. 2 is a perspective view showing the coupling of a vacuum chamberwith a door, according to the present invention;

FIG. 3 is a sectional view taken along line A-A of FIG. 2; and

FIG. 4 is an exploded sectional view of FIG. 3.

DESCRIPTION OF REFERENCE CHARACTERS OF IMPORTANT PARTS

10: plasma sterilizer 20: chamber 30: door 32: groove 34: fastening hole40: base plate 60: hinge assembly 70: guide plate 72: groove 74: throughhole 82: fastening member 84: guide bushing 84a: hole 84b: first part84c: second part 90: elastic member 92: space

Best Mode

Hereinafter, the preferred embodiment of the present invention will bedescribed in detail with reference to the accompanying drawings.

FIG. 2 is a perspective view showing the coupling structure of a doorfor a vacuum chamber, according to the present invention, FIG. 3 is asectional view taken along line A-A of FIG. 2, and FIG. 4 is an explodedsectional view of FIG. 3.

As shown in the drawings, a plasma sterilizer is provided with a chamber20 which creates a vacuum so as generate plasma, and a door 30 which ismounted to one surface of the chamber 20 and is used to put articles tobe sterilized, for example, medical instruments, into the chamber 20.

The chamber 20 is hermetically sealed, except for an opening which isprovided in one surface of the chamber. The door 30 is mounted so as toopen or close the opening.

In a detailed description, a base plate 40, which is open at a centralportion thereof, is mounted to the opening of the chamber 20. The door30 is provided on the front of the base plate 40 so as to open or closethe opening which is formed in the central portion of the base plate 40.

The base plate 40 is part of a frame for supporting the chamber 20, andis secured to the chamber. Guide plates 70 are rotatably mounted to onesurface of the base plate 40, and are fastened to the door 30.

That is, hinge assemblies 60 are provided on one end of the base plate40. Each guide plate 70 is rotatably coupled at one end thereof to thecorresponding hinge assembly 60. The guide plate 70 is fastened to thedoor via a plurality of fastening units 80.

Meanwhile, grooves 32, each having a predetermined depth, are providedat regular intervals in the outer surface of the door 30 which contactseach guide plate 70. A fastening hole 34 is formed in the center of eachgroove 32 and is deeper than the groove.

Further, grooves 72, each having a predetermined depth, are provided onthe inner surface of each guide plate 70 which contacts the outersurface of the door 30, and correspond to the grooves 32 in the door 30.

Thus, when each guide plate 70 contacts the door 30, the grooves 32 and72 overlap each other, thus defining a space 92 having a predeterminedsize.

Further, a through hole 74 is formed in the center of each groove 72 ineach guide plate 70, so that a guide bushing 84 and a fastening member82, which will be described below, pass through the through hole.

The guide bushing 84 has a “T”-shaped section, and includes a first part84 b and a second part 84 c. The first part passes through thecorresponding through hole 74 in each guide plate 70, and slides apredetermined interval in the space 92. The second part has a largerdiameter than the through hole 74 in the guide plate 70, so that thesecond part is stopped by the outer surface of the guide plate 70.

A hole 84 a is formed in the guide bushing 84 so that the fasteningmember 82 passes through the guide bushing. Thus, after the fasteningmember 82 is inserted into the hole 84 a in the guide bushing 84, theend of the fastening member 82 is fastened to the correspondingfastening hole 34 of the door 30. When the end of the fastening member82 is completely fastened to the corresponding fastening hole 34 of thedoor 30, the second part 84 c of the guide bushing 84 is spaced apartfrom the outer surface of the guide plate 70 by a predeterminedinterval, thus defining a gap G between the outer surface of the guideplate and the second part. The reason why this gap is formed will bedescribed below.

Further, an elastic member 90 is installed in each space 92, which isdefined between the grooves 32 and 72 in the door 30 and each guideplate 70, and surrounds the outer surface of the first part 84 b of theguide bushing 84. One end of the elastic member 90 is supported by theinner surface of each groove 32 in the door 30, while the other end ofthe elastic member is supported by the inner surface of thecorresponding groove 72 in each guide plate 70.

Any member may be used as the elastic member 90, as long as the memberhas predetermined elasticity. It is preferable that a coil spring beused as the elastic member.

Further, blocks 86 are mounted to each guide plate 70 via bolts. Eachblock surrounds the corresponding guide bushing 84 so as to guide thesliding motion of the guide bushing, and increases the strength of theguide plate 70.

The operation of the door for the vacuum chamber, which is constructedas described above, will be described below.

First, the door 30 is opened to put an article to be sterilized into thechamber 20. In this state, the door 30 is closed again so as to seal thechamber 20. Thereafter, a vacuum is created in the chamber 20, thusgenerating plasma.

At this time, each guide plate 70, which is fastened to the door 30 viathe fastening units 80, rotates around the corresponding hinge assembly60, which is mounted to one end of the base plate 40. As the guide platerotates, the door may be opened or closed.

When a vacuum is created in the chamber 20, the door 30 is pulledtowards the chamber 20 by external atmospheric pressure.

The fastening members 82 are fastened to the corresponding fasteningholes 34, which are formed in the upper and lower edges of the door 30.As the door 30 is pulled, the fastening members 82 move inwards.

At this time, each elastic member 90, which is installed in the space 92defined between each of the grooves 32 in the door 30 and thecorresponding groove 72 in each guide plate 70, is extended as the door30 is pulled. Simultaneously, each guide bushing 84, through which thefastening member 82 passes, is also pulled inwards by a predeterminedinterval.

As described above, the maximum interval by which each guide bushing 84is pulled is equal to the gap G which is defined between the guide plate70 and the second part 84 c of the guide bushing 84.

That is, when the door 30 is pulled towards the chamber 20 by the vacuumpressure in the chamber 20, the fastening members 82 are also pulledinwards. At this time, each elastic member 90 is extended, and eachguide bushing 84, through which the fastening member 82 passes, is movedinwards. Thereby, each guide plate 70 remains in a fixed position.

Thus, a large load is not applied to each hinge assembly 60, which iscoupled to the corresponding guide plate 70 and the base plate 40.

Further, when the vacuum in the chamber 20 is released, so that thechamber 20 has atmospheric pressure, the door 30 is pushed outwards bythe elastic restoring force of each elastic member 90, and is in closecontact with each guide plate 70. Simultaneously, each fastening member82 is pushed outwards along with the corresponding guide bushing 84.Thus, the second part 84 c of each guide bushing 84 is spaced apart fromthe corresponding guide plate 70 by a predetermined interval.

While the invention has been described with reference to a vacuumchamber for a plasma sterilizer, as an example, the present inventionmay be applied to any vacuum chamber constructed such that a door ismounted to one surface of the vacuum chamber so as to open or close it.

1. A door for a vacuum chamber, comprising: a chamber having in onesurface thereof an opening; a door rotated to open or close the openingof the chamber; and a guide plate fastened to an outer surface of thedoor in such a way as to be spaced apart from the door by apredetermined interval, the guide plate being rotatably coupled at oneend thereof to a hinge assembly.
 2. The door according to claim 1,wherein the door comprises fastening holes having a predetermined depthat regular intervals, and the guide plate comprises through holescorresponding to the fastening holes, so that a fastening member passesthrough a corresponding through hole and is secured at an end thereof tothe corresponding fastening hole, thus fastening the guide plate to thedoor.
 3. The door according to claim 1, wherein first grooves are formedat regular intervals in a surface of the door contacting the guideplate, and second grooves are formed in the guide plate to correspond tothe first grooves in the door, so that, when the guide plate contactsthe door, a space having a predetermined size is defined between thefirst and second grooves.
 4. The door according to claim 2, wherein eachof the first grooves in the door is formed around a correspondingfastening hole to have a predetermined depth, and each of the secondgrooves in the guide plate is formed around a corresponding through holeto have a predetermined depth.
 5. The door according to claim 3, whereinan elastic member is installed in the space, is secured at a first endthereof to an inner surface of each of the first grooves in the door,and is secured at a second end thereof to an inner surface of each ofthe second grooves in the guide plate.
 6. The door according to claim 5,wherein the elastic member comprises a coil spring.
 7. The dooraccording to claim 2, further comprising: a guide hushing having a holethrough which the fastening member passes, and comprising: a first partpassing through a corresponding through hole in the guide plate, andsliding a predetermined interval in the space; and a second part havinga diameter larger than the through hole in the guide plate, and stoppedby an outer surface of the guide plate.
 8. The door according to claim7, wherein, when the end of the fastening member is completely fastenedto each of the first grooves in the door, a predetermined gap is definedbetween the second part of the guide bushing and the outer surface ofthe guide plate.
 9. The door according to claim 7, wherein a block isfastened to the guide plate, increases strength of the guide plate, andhas a hole for guiding the guide bushing.
 10. The door according toclaim 1, wherein a base plate, having in a central portion thereof anopening, is provided on a front of the opening of the chamber, and thedoor is rotated to open or close the opening of the base plate and theopening of the chamber.
 11. The door according to claim 10, wherein thehinge assembly is mounted to an end of the base plate, and an end of theguide plate is rotatably coupled to the hinge assembly.
 12. The dooraccording to claim 3, wherein each of the first grooves in the door isformed around a corresponding fastening hole to have a predetermineddepth, and each of the second grooves in the guide plate is formedaround a corresponding through hole to have a predetermined depth.